2004 YAMAHA YZF-R1S warning

7-4
30: Lean angle cut-off switch
(latch up detected)
41: Lean angle cut-off switch
(open or short circuit)
50: ECU internal malfunction
(memory check error)
FUEL INJECTION SYSTEMFI
EAS00899
ECU’S SELF-DIAGNOSTIC FUNCTION
The ECU is equipped with a self-diagnostic function in order to ensure that the engine control system is
operating normally. If this function detects a malfunction in the system, it immediately operates the en-
gine under substitute characteristics and illuminates the engine trouble warning light to alert the rider
that a malfunction has occurred in the system. Once a malfunction has been detected, a fault code is
stored in the memory of the ECU.

To inform the rider that the fuel injection system is not functioning, the engine trouble warning light
flashes when the start switch is being pushed to start the engine.

If a malfunction is detected in the system by the self-diagnostic function, this mode provides an ap-
propriate substitute characteristic operation, and alerts the rider of the detected malfunction by illumi-
nating an engine trouble warning light.

After the engine has been stopped, the fault code number appears from the lowest value in order of
precedence on the LCD meter. Once a fault code has been displayed, it remains stored in the memory
of the ECU until it is deleted.
EAS00900
Engine trouble warning light indication and FI system operating condition
Warning light
indication
ECU’s operationFI operationVehicle operation
Flashing*Warning provided
when unable to start
engineOperation stoppedUnable
Remains ONMalfunction detectedOperated with
substitute
characteristics
in accordance with the
description of the
malfunctionAble / Unable depend-
ing on the self-diag-
nostic fault code
* The warning light flashes when any one of the conditions listed below is present and the start switch is
pushed.
11: Cylinder identification sensor
12: Crankshaft position sensor
19: Sidestand switch
(open circuit in wire to ECU)
EAS00901
Checking for a defective engine trouble warning light bulb
The engine trouble warning light comes on for 1.4 seconds after the main switch has been turned “ON”
and when the start switch is being pushed. If the warning light does not come on under these condi-
tions, the warning light bulb may be defective.
ProCarManuals.com

7-5
FUEL INJECTION SYSTEMFI
SUBSTITUTE CHARACTERISTICS OPERATION CONTROL (FAIL-SAFE ACTION)
If the ECU detects an abnormal signal from a sensor while the vehicle is being driven, the ECU illumi-
nates the engine trouble warning light and provides the engine with alternate operating instructions
that are appropriate for the type of malfunction.
When an abnormal signal is received from a sensor, the ECU processes the specified values that are
programmed for each sensor in order to provide the engine with alternate operating instructions that
enable the engine to continue to operate or stop operating, depending on the conditions.
The ECU takes fail-safe actions in two ways: one in which the sensor output is set to a prescribed value,
and the other in which the ECU directly operates an actuator. Details on the fail-safe actions are given
in the table below.
FAIL-SAFE ACTIONS TABLE
Fault
Code No.ItemSymptomFail-safe actionAble / unable
to startAble / unable
to drive
11
Cylinder identification
sensorNo normal signals are received from
the cylinder identification sensor.Continues to operate the engine based
on the results of the cylinder
identification that existed up to that
point.
UnableAble
12Crankshaft position
sensorNo normal signals are received from
the crankshaft position sensor.
Stops the engine (by stopping the
injection and ignition).UnableUnable
13
14Intake air pressure
sensor (open or short
circuit) (pipe system)Intake air pressure sensor-open or
short circuit detected.
Faulty intake air pressure sensor
system.
Fixes the intake air pressure to
101.3 kpa.
AbleAble
15
16Throttle position sensor
(open or short circuit)
(stuck)Throttle position sensor-open or short
circuit detected.
Fixes the throttle position sensor to
fully open.AbleAble
17EXUP servo motor
potention
(open or short circuit)EXUP servo motor potention-open or
short circuit detected.
Turn the EXUP servo motor toward
the open side for 3 seconds and then
stop it.AbleAble
18
EXUP servo motor (lock)A lock of the EXUP servo motor is
detected.
Perform the preventive control
against motor locking.
Perform the lock release operation
twice every 100 seconds.
AbleAble
19Sidestand switch (open
circuit in wire to ECU)Open circuit in the input line of ECU
No.15 terminal is detected when the
start switch is pressed.-- (No start)UnableUnable
20Intake air pressure
Atmospheric pressureDefective values are detected due to
the internal malfunction
Fixes the intake air pressure and
atmospheric pressure to 101.3 kpa.AbleAble
21Coolant temperature
sensorCoolant temperature sensor-open or
short circuit detected.
Fixes the coolant temperature to
60C.AbleAble
22Intake temperature
sensorIntake temperature sensor-open or
short circuit detected.
Fixes the intake temperature to 20C.AbleAble
23Atmospheric pressure
sensorAtmospheric pressure sensor-open or
short circuit detected.
Fixes the atmospheric pressure to
101.3 kpa.AbleAble
33
34
35
36
Faulty ignitionOpen circuit detected in the primary
lead of the ignition coil.
Cut the injection of other cylinder in
the same group with the cylinder that
the error is detected.
(Example: when the #1 cylinder is
detective, cut the injection of #1 and
#4 cylinders, when the #2 cylinder is
detective, cut the injection of #2 and
#3 cylinders).
Turn on the power to the air induction
solenoid to always cut-off the air.
Able
(depending
on the num-
ber of faulty
cylinders)Able
(depending
on the num-
ber of faulty
cylinders)
30
41Lean angle cut-off
switch (latch up
detected) (open or short
circuit)Lean angle cut-off switch-open or short
circuit detected.
Turns OFF the fuel injection system
relay of the fuel system.
UnableUnable
42Speed sensor, neutral
switchNo normal signals are received from the
speed sensor; or, an open or short
circuit is detected in the neutral switch.
Fixes the gear to the top gear.AbleAble
43Fuel system voltage
(monitor voltage)The ECU is unable to monitor the
battery voltage (an open circuit in the
line to the ECU).
Fixes the battery voltage to 12 V.AbleAble
44
Error in writing the
amount of CO
adjustment on
EEPROMAn error is detected while reading or
writing on EEPROM (CO adjustment
value).--
AbleAble
ProCarManuals.com

7-6
FUEL INJECTION SYSTEMFI
Fault
Code No.ItemSymptomFail-safe actionAble / unable
to startAble / unable
to drive
46Vehicle system power
supply (Monitor voltage)Power supply to the FI system is not
normal.--AbleAble
47Sub-throttle servo motor
potention (open or short
circuit)sub-throttle servo motor potention-
open or short circuit detected.
Turn the sub-throttle servo motor
toward the close side for 4 seconds
and then stop it.AbleAble
48
Sub-throttle servo motor
(lock)A lock of the sub-throttle servo motor is
detected.
Perform the preventative control
against motor locking.
(Perform the lock release operation
twice every 100 seconds.)
AbleAble
50ECU internal
malfunction (memory
check error)Faulty ECU memory. When this
malfunction is detected, the code
number might not appear on the meter.--UnableUnable
—
Start unable warningRelay is not turned ON even if the crank
signal is input while the start switch is
turned ON.
When the start switch is turned ON
while an error is detected with the fault
code of No.11, 12, 19, 30, 41 or 50.Engine trouble warning light flashes
when the start switch is turned ON.
UnableUnable
Communication error with the meter
Fault
Code No.ItemSymptomFail-safe actionAble / unable
to startAble / unable
to drive
Er-1ECU internal malfunction
(output signal error)No signals are received from the ECU.–UnableUnable
Er-2ECU internal malfunction
(output signal error)No signals are received from the ECU
within the specified duration.–UnableUnable
Er-3ECU internal malfunction
(output signal error)Data from the ECU cannot be received
correctly.–UnableUnable
Er-4ECU internal malfunction
(input signal error)Non-registered data has been received
from the meter.–UnableUnable
ProCarManuals.com

7-7
Engine operation is not normal or the engine trouble warning light is on.
* Engine trouble warning light may not come on even if the engine operation is not normal.
The engine trouble warning light comes on.
Check the fault code number displayed on the me-
ter.
Identify the probable cause of malfunction. (Refer
to the “Diagnostic fault code table”.)
Check and repair the probable case of malfunc-
tion.
Fault code No.
appearFault code No.
disappear
Check and repair.
(Refer to “TROU-
BLESHOOTING DE-
TAILS”.)
Monitor the operation
of the sensors and
actuators in the diag-
nostic mode. (Refer
to “Diagnostic mode
table” in chapter 7)Check and repair.
(Refer to “FAIL-SAFE
ACTIONS TABLE”.)
Perform ECU reinstatement action. (Refer to “Re-
instatement method” in “TROUBLESHOOTING
DETAILS”.)
Turn the main switch to “OFF”, turn the main switch
back to “ON”, and then check if the fault code num-
ber is still displayed.
Erasing the malfunction history:*
The malfunction history is stored even if the main
switch is turned OFF.
The malfunction history must be erased in the
diagnostic mode. (Refer to the “Diagnostic mode
table (Diagnostic code No.62)”)Repairs completed
The engine trouble warning light does not come
on.
Check the operation of following sensors and ac-
tuators in the diagnostic mode (Refer to “Diagnos-
tic mode table” in chapter 7.)
Malfunction of en-
gineDefective sensor
or actuator
Check and repair
the inner parts of
engine. (Refer to
Chapter 5)Check and repair
the corresponding
sensor or actua-
tor.
* Operated when the engine trouble warning light is on.
Fault code
number displayed
Fault code number not displayed
OKNG
OK
OK
Check the engine condition.
OK NG
01: Throttle position
sensor (throttle
angle)
03: Intake air pressure
07: Vehicle speed pulse
09: Fuel system volt-
age (battery bolt)
21: Neutral switch
30: Ignition coil #1
31: Ignition coil #232: Ignition coil #3
33: Ignition coil #4
36: Injector #1
37: Injector #2
38: Injector #3
39: Injector #4
48: Al system solenoid
53: EXUP servo motor
56: Sub-throttle servo
motor
FUEL INJECTION SYSTEMFI
EAS00904
TROUBLESHOOTING CHART
ProCarManuals.com

7-12
FUEL INJECTION SYSTEMFI
NOTE: Diagnostic mode table
Switch the meter display from the regular mode to the diagnosis mode. To switch the display, refer to
“DIAGNOSTIC MODE”.

Check the intake air temperature and coolant temperature as close as possible to the intake air tem-
perature sensor and the coolant temperature sensor respectively.

If it is not possible to check it with an atmospheric pressure gauge, judge it by using 101.3 kPa as the
standard.

If it is not possible to check the intake air temperature, use the ambient temperature as reference.
Diagnostic
codeItemDescription of actionData displayed on meter
(reference value)
01
Throttle angleDisplays the throttle angle.

Check with throttle fully closed.

Check with throttle fully open.0
125 degrees

Fully closed position (15
18)

Fully open position (95
100)
02
Atmospheric
pressureDisplays the atmospheric pressure.
* Use an atmospheric pressure gauge to check the
atmospheric pressure.Compare it to the value
displayed on the meter.
03
Intake air pressureDisplays the intake air pressure.
Engine stop switch is on.
* Generate the pressure difference by cranking the engine
with the starter, without actually starting the engine.
Not cranking-atmospheric
pressure

Cranking-intake air pressure It
changes at the value whitch is
smaller than in the atomo-
spheric pressure.
05Intake temperatureDisplays the intake air temperature.
* Check the temperature in the air cleaner case.Compare it to the value
displayed on the meter.
06Coolant temperatureDisplays the coolant temperature.
* Check the temperature of the coolant.Compare it to the value
displayed on the meter.
07
Vehicle speed pulseDisplays the accumulation of the vehicle pulses that are
generated when the tire is spun.(0
999; resets to 0 after 999)
OK if the numbers appear on
the meter.
08Lean angle cut-off
switchDisplays the lean angle cut-off switch values.Upright: 0.4
1.4 V
Overturned: 3.7
4.4 V
09Fuel system voltage
(battery voltage)Displays the fuel system voltage (battery voltage).
Engine stop switch is on.0
18.7 V
Normally, approximately 12.0 V
20Sidestand switchDisplays that the switch is ON or OFF. (When the gear is in a
position other than neutral.)Stand retracted: ON
Stand extended: OFF
21Neutral switchDisplays that the switch is ON or OFF.Neutral: ON
In gear: OFF
30
Ignition coil #1After the engine stop switch has been turned from OFF to
ON, it actuates ignition coil #1 for five times every second
and illuminates the engine trouble warning light.
* Connect an ignition checker.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check that spark is generated,
5 times with the engine stop
switch ON.
31
Ignition coils #2After the engine stop switch has been turned from OFF to
ON, it actuates ignition coil #2 for five times every second
and illuminates the engine trouble warning light.
* Connect an ignition checker.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check that spark is generated,
5 times with the engine stop
switch ON.
ProCarManuals.com

7-13
FUEL INJECTION SYSTEMFI
Diagnostic
codeItemDescription of actionData displayed on meter
(reference value)
32
Ignition coil #3After the engine stop switch has been turned from OFF to
ON, it actuates ignition coil #3 for five times every second
and illuminates the engine trouble warning light.
* Connect an ignition checker.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check that spark is generated,
5 times with the engine stop
switch ON.
33
Ignition coil #4After the engine stop switch has been turned from OFF to
ON, it actuates ignition coil #4 for five times every second
and illuminates the engine trouble warning light.
* Connect an ignition checker.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check that spark is generated,
5 times with the engine stop
switch ON.
36
Injector #1After the engine stop switch has been turned from OFF to
ON, it actuates the injector #1 five times every second and
illuminates the engine trouble warning light.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check the operating sound of
the injector five times with
engine stop switch ON.
37
Injector #2After the engine stop switch has been turned from OFF to
ON, it actuates the injector #2 five times every second and
illuminates the engine trouble warning light.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check the operating sound of
the injector five times with
engine stop switch ON.
38
Injector #3After the engine stop switch has been turned from OFF to
ON, it actuates the injector #3 five times every second and
illuminates the engine trouble warning light.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check the operating sound of
the injector five times with
engine stop switch ON.
39
Injector #4After the engine stop switch has been turned from OFF to
ON, it actuates the injector #4 five times every second and
illuminates the engine trouble warning light.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check the operating sound of
the injector five times with
engine stop switch ON.
48
AI system solenoidAfter the engine stop switch has been turned from OFF to
ON, it actuates the AI system solenoid five times every
second and illuminates the engine trouble warning light.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check the operating sound of
the AI system solenoid 5 times
with the engine stop
switch ON.
50
Fuel injection system
relayAfter the engine stop switch has been turned from OFF to
ON, it actuates the fuel injection system relay five times
every second and illuminates the engine trouble warning
light (the light is OFF when the relay is ON, and the light is
ON when the relay is OFF).
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check the fuel injection system
relay operating sound 5 times
with the engine stop
switch ON.
51
Radiator fan motor
relayAfter the engine stop switch has been turned from OFF to
ON, it actuates the radiator fan motor relay five times every
5 seconds and illuminates the engine trouble warning light.
(ON 2 seconds, OFF 3 seconds)
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check the radiator fan motor
relay operating sound 5 times
with the engine stop
switch ON.
(At that time, the fan motor
rotates.)
ProCarManuals.com

7-14
FUEL INJECTION SYSTEMFI
Diagnostic
codeItemDescription of actionData displayed on meter
(reference value)
52
Headlight relay 1After the engine stop switch has been turned from OFF to
ON, it actuates the headlight relay five times every
5 seconds and illuminates the engine trouble warning light.
(ON 2 seconds, OFF 3 seconds)
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Check the headlight relay
operating sound 5 times with the
engine stop switch ON.
(At that time, the headlight turns
ON.)
53
EXUP servo motorAfter the engine stop switch has been turned from OFF to
ON, it actuates the servo motor turns to open side and to
close side.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back ON.Turn on the engine trouble
warning light while servo motor
is operated. (Operating angle is
displayed on the LCD meter)
56
Sub-throttle servo
motorAfter the engine stop switch has been turned from OFF to
ON, it actuates the servo motor turns to open side and to
close side.
* If the engine stop switch is ON, turn it OFF once, and then
turn it back on.Turn on the engine trouble warn-
ing light while servo motor is op-
erated (Operating angle is dis-
played on the LCD meter).
60
EEPROM fault code
display
Transmits the abnormal portion of the data in the E2PROM
that has been detected as a self-diagnostic fault code 44.

If multiple malfunctions have been detected, different
codes are displayed at 2-second intervals, and this
process is repeated.(01
04) Displays the cylinder
number.
(00) Displays when there is no
malfunction.
61
Malfunction history
code display
Displays the codes of the history of the self-diagnosis
malfunctions (i.e., a code of a malfunction that occurred
once and which has been corrected).

If multiple malfunctions have been detected, different
codes are displayed at 2-second intervals, and this
process is repeated.11
50
(00) Displays when there is no
malfunction.
62
Malfunction history
code erasure
Displays the total number of codes that are being detected
through self diagnosis and the fault codes in the past
history.

Erases only the history codes when the engine stop switch
is turned from OFF to ON. If the engine stop switch is ON,
turn it OFF once, and then turn it back ON.00
25
(00) Displays when there is no
malfunction.
70Control number
Displays the program control number.00
255
ProCarManuals.com

7-24
FUEL INJECTION SYSTEMFI
Intake air temperature sensor
resistance
2.21
2.69 kΩ at 20C (68F) Tester positive probe
brown / white
Tester negative probe
black / blue
1
2
12

Handle the intake air temperature sensor
with special care.

Never subject the intake air temperature sen-
sor to strong shocks. If the intake air temper-
ature sensor is dropped, replace it.
WARNING
Fault code No.22SymptomOpen or short circuit detected from the intake temperature sensor.
Used diagnostic code No. 05 (intake temperature sensor)
OrderInspection operation item and probable
causeOperation item and countermeasureReinstatement
method
1Connected condition of connector
Inspect the coupler for any pins that
may have pulled out.
Check the locking condition of the
coupler.If there is a malfunction, repair it and connect it
securely.
Intake temperature sensor coupler
Main wiring harness ECU coupler
Sub-wire harness couplerReinstated by
turning the
main switch
ON.
2Open or short circuit in wiring harness
and / or sub lead.Repair or replace if there is an open or short
circuit.
Between sensor coupler and ECU coupler
Black / Blue – Black / Blue
Brown / White – Brown / White
3Defective intake temperature sensor.Execute the diagnostic mode (Code No.05).
Replace if defective.
1. Remove the intake air temperature sensor
from the air filter case.
2. Connect the pocket tester (Ω  100) to the
intake air temperature sensor terminal as
shown.
3. Measure the intake air temperature sensor
resistance.
4. Is the intake air temperature sensor OK?
ProCarManuals.com